If you're using SP2, it has to be a BIOS limitation. Also, the drive can be recognised as 300gb in windows in an external enclosure, so it HAS to be a bios issue. I know the hardware will support 48bit LBA, I was even able to get a bios update for my buddy's GA-7VX mobo to support a 200gb seagate drive. It might be listed in the bios as BIG LBA, or 48 BIT LBA, either way, it should be enabled, or on. If the option isn't listed, it might be that you need a bios update. You need to know the EXACT make/model of your mobo for that. If you screw up, and flash it with a wrong bios, you're SCREWED. So, if you need to update it, get it RIGHT. One thing to try before you update the mobo's bios is to update your IDE drivers. Usually, if the IDE drivers don't support 48 bit LBA, it recognises the drive, you just get corruption if you exceed 128gb. The IDE drivers might be part of the chipset drivers, so you might have to install the whole package, which might in turn hose your video drivers . The mobo is new enough to support a sempron chip, which means it should definetly support a 300gb hard drive.